Scientists have studied animals’ feelings for hundreds of years. However, the past research mainly focused on animals’ negative feelings, such as expressions of pain and fear. This can help reduce animals’ suffering, but it doesn’t tell what brings them happiness.

Now some scientists are working together to better understand animals’ joy. They are trying to measure (测量) joy in animals in a new study. The scientists define (下定义) joy as a strong positive feeling which is caused by an event, such as seeing a friend or a favorite food. They have created a set of ways to measure the feeling in different animals. The scientists want to make sure that the final result is not from just guessing animals’ mind, but from scientific research.

Some signs of joy are connected with actions. For example, some scientists have noticed that chimpanzees (黑猩猩) make laugh-like sounds while they are playing. Other scientists have noticed that dolphins (海豚) produce joyful sounds when happy things happen to them.

However, actions do not tell the whole story. Horses seem to be happily playing, but they may actually have the opposite feeling: they are downcast. So the scientists are also examining animals’ brain chemistry and studying their body temperature changes to help tell if the animals are truly happy.

Learning about joy in animals can improve the care of animals. And the new study about animals’ happiness can also help better understand humans’ happiness.

1.1. What does the new study about animals focus on?

A Their fear.

B Their happiness.

C Their food.

D Their friendship.

解析：选B。- 题型：细节理解题 - 解析：根据第二段 “Now some scientists are working together to better understand animals' joy…They are trying to measure joy in animals in a new study.” 可知这项新研究聚焦动物的快乐。fear 恐惧、food 食物、friendship 友谊均不是新研究核心。

2.2. Why are chimpanzees and dolphins mentioned in paragraph 3?

A To record the challenge of studying animals.

B To explain the ways of making happy sounds.

C To show the connection between joy and actions.

D To tell the differences between two kinds of animals.

解析：选C。- 题型：推理判断题（例证作用） - 解析：第三段主旨句 “Some signs of joy are connected with actions.”，后面举黑猩猩、海豚的例子，就是为证明喜悦和行为之间存在联系。A 记录研究的挑战；B 解释发出快乐声音的方式；D 说明两种动物的区别，均不符合段落逻辑。

3.3. What does the underlined word “downcast” in paragraph 4 mean?

A Sad.

B Calm.

C Moved.

D Surprised.

解析：选A。- 题型：词义猜测题 - 解析：第四段 “seem to be happily playing, but they may actually have the opposite feeling”，but 表转折，opposite feeling 意为相反的情绪，和 happy 相反就是 sad（悲伤、情绪低落）。calm 冷静的；moved 感动的；surprised 惊讶的，不符合。

4.4. What does the writer think of the new study?

A It makes people get close to nature.

B It improves animals’ daily behavior.

C It encourages people to keep animals.

D It benefits both animals and humans.

解析：选D。- 题型：观点态度题 - 解析：最后一段 “Learning about joy in animals can improve the care of animals. And the new study…can also help better understand humans’ happiness.” 说明该研究既有益于动物，也有益于人类。A 让人们亲近自然；B 改善动物日常行为；C 鼓励人们饲养动物，文中无对应信息。